Possible Causes
WARNING: This page is about a different car, the 2003 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
This DTC uses two-trip detection logic. DTC is set when both oxygen sensors have nearly the same waveform pattern after engine and catalytic converter are at normal operating temperature and vehicle is driven at 55 MPH for at least 5 minutes. Possible causes are:
- Exhaust system leak.
- Defective heated oxygen sensor.
- Defective catalytic converter.